text: /*=========================================================================
   *
   *  Copyright NumFOCUS
   *
   *  Licensed under the Apache License, Version 2.0 (the "License");
   *  you may not use this file except in compliance with the License.
   *  You may obtain a copy of the License at
   *
   *         http://www.apache.org/licenses/LICENSE-2.0.txt
   *
   *  Unless required by applicable law or agreed to in writing, software
   *  distributed under the License is distributed on an "AS IS" BASIS,
   *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   *  See the License for the specific language governing permissions and
   *  limitations under the License.
   *
   *=========================================================================*/
  #ifndef itkTorusInteriorExteriorSpatialFunction_hxx
  #define itkTorusInteriorExteriorSpatialFunction_hxx
  
  #include "itkTorusInteriorExteriorSpatialFunction.h"
  
  namespace itk
  {
  template <unsigned int VDimension, typename TInput>
  TorusInteriorExteriorSpatialFunction<VDimension, TInput>::TorusInteriorExteriorSpatialFunction()
  
  {
    m_Origin.Fill(0.0);
  }
  
  template <unsigned int VDimension, typename TInput>
  auto
  TorusInteriorExteriorSpatialFunction<VDimension, TInput>::Evaluate(const InputType & position) const -> OutputType
  {
    double x = position[0] - m_Origin[0];
    double y = position[1] - m_Origin[1];
    double z = position[2] - m_Origin[2];
  
    double k = std::pow(m_MajorRadius - std::sqrt(x * x + y * y), 2.0) + z * z;
  
    if (k <= (m_MinorRadius * m_MinorRadius))
    {
      return true;
    }
    else
    {
      return false;
    }
  }
  
  template <unsigned int VDimension, typename TInput>
  void
  TorusInteriorExteriorSpatialFunction<VDimension, TInput>::PrintSelf(std::ostream & os, Indent indent) const
  {
    Superclass::PrintSelf(os, indent);
  
    unsigned int i;
  
    os << indent << "Origin: [";
    for (i = 0; i < VDimension - 1; ++i)
    {
      os << m_Origin[i] << ", ";
    }
    os << "]" << std::endl;
  
    os << indent << "Major radius: " << m_MajorRadius << std::endl;
  
    os << indent << "Minor radius: " << m_MinorRadius << std::endl;
  }
  } // end namespace itk
  
  #endif
  